4 Bars

There are 4 bars, each a different colour. Your aim is to fill or empty one of the bars. At the start of each game you are told which one to fill or empty. There are 4 buttons. Each one allows you to increase or decrease the value of the associated bars. But be careful - whichever button you tap every bar is affected by the values of their associated buttons. Study the buttons carefully to figure out how to reach your target. No ads or In-App purchases and there never will be.